Cain formed an elite squad of demonic killers known as the [[Knights of Hell]]. The Blade is the only thing in existence capable of killing them. After Cain left the Knights for love, they kidnapped the woman -- [[Colette Mullen]]. In retribution Cain killed them all, except [[Abaddon]], who was possessing the body of Colette, and escaped as Cain drove the First Blade into her body. Afterwards Cain made a promise to a dying Colette that he would give up killing, with the First Blade being indestructible, Cain was forced to throw it into the ocean to rid himself of it.
After Abaddon returned and began trying to take over Hell, Dean and the King of Hell, [[Crowley]], began a search for the First Blade. After Cain gave Dean the Mark of Cain, he told them where to look. Eventually, they tracked the First Blade to former [[Men of Letters|Man of Letters]] [[Cuthbert Sinclair]] though Crowley took the First Blade rather than let Dean keep it. After being captured by Abaddon, Crowley led Dean to the First Blade and Dean managed to kill Abaddon with it. After Dean briefly turned into a demon after being killed by [[Metatron]] while attempting to use the First Blade on him, Crowley took it back in exchange for giving Sam Dean's location and hid it in a crypt in Guam. Crowley retrieved the First Blade after Metatron told the Winchesters that it could be used as part of a cure for the Mark of Cain, but refused to hand it over until they had the rest of the cure. After Cain started murdering again, Crowley lent Dean the First Blade in exchange for it being
returned to him. Cain eventually got the First Blade back, but Dean managed to overpower him and kill him in the end. Rather than returning the First Blade to Crowley, Dean gave it to [[Castiel]] who hid it somewhere safe. When the Mark of Cain is removed by Rowena and [[The Darkness]] is released, the First Blade becomes useless.